Replacement Rear Spring--Why So High??
Thread Starter
Burning Brakes
Joined: Apr 2000
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From: Minnesota
Replacement Rear Spring--Why So High??
From looking at Posts over the years about rear spring replacement--it seems that many who have replaced their springs complain about the rear end sitting high. Why is this--obviously our cars didn't come from the factory this way--what is with the suppliers of these springs? I replaced mine recently with a 9 leaf which is stock and the thing sat up high enough it looked like a 4 wheel drive mudder--I pulled that out and changed to a 7 leaf--much better but it still a little high--countless phones with the supplier and not much help--what gives?
SEMPER FI--1970 Dave
SEMPER FI--1970 Dave
Thread Starter
Burning Brakes
Joined: Apr 2000
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From: Minnesota
Originally Posted by Redshark6974
have you tried longer bolts?Bolts long enough would have to be a minimum of about 14 inches long--the ride height was just shy of 35 1/2 inches--and yes I have heard of the longer spring bolts?
Burning Brakes
Joined: Oct 2004
Posts: 1,038
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From: Grants Pass Oregon
Wow Nelly!
35.5 inches? 
That Is a 4X4........From the floor to the top of the front or rear wheel well is 27 inches....Period. The factory assembly manual gives varing hights like 26 and 3/4 or 27 and 1/4 but at the bottom of the page it says specificly the delivery objective is 27 inches.
So with varying wheel and tire combinations you might see an inch to 2 inch difference, but definatly not 35.5 inches. Where the helll were you taking that measurement from?
That Is a 4X4........From the floor to the top of the front or rear wheel well is 27 inches....Period. The factory assembly manual gives varing hights like 26 and 3/4 or 27 and 1/4 but at the bottom of the page it says specificly the delivery objective is 27 inches.So with varying wheel and tire combinations you might see an inch to 2 inch difference, but definatly not 35.5 inches. Where the helll were you taking that measurement from?
Melting Slicks
Joined: Jan 2004
Posts: 2,672
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From: New Cumberland PA
If the spring was made to OEM specs, longer spring bolts should not be needed. I believe your question is why the manufactures of replacement spring cannot duplicate a similiar spring or at least ship a spring that retains the same ride height as the original. I do not have any answers to that. I would guess it may be a lack of quality control. They make a spring and assume it's perfect when in fact there are many that are out of spec.
In your case, changing to an 8" bolt may provide a solution to a problem created by the spring manufacture. The TRW composite spring is totally different in that they ship 8" bolts knowing that they will be needed. The problem with some of these springs is that the 8" bolts still do not provide enough length to lower the rear to an acceptable height. 10" bolts are needed which causes other issuses and may be unsafe due to tire and suspension issues. Muskegon is in the process of doing some testing and is to report back to the forum in the next few days according to the post in this thread, http://forums.corvetteforum.com/show...&page=18&pp=20 .
In your case, changing to an 8" bolt may provide a solution to a problem created by the spring manufacture. The TRW composite spring is totally different in that they ship 8" bolts knowing that they will be needed. The problem with some of these springs is that the 8" bolts still do not provide enough length to lower the rear to an acceptable height. 10" bolts are needed which causes other issuses and may be unsafe due to tire and suspension issues. Muskegon is in the process of doing some testing and is to report back to the forum in the next few days according to the post in this thread, http://forums.corvetteforum.com/show...&page=18&pp=20 .
Last edited by mandm1200; Feb 23, 2005 at 03:33 PM.
Melting Slicks
Joined: Jan 2004
Posts: 2,672
Likes: 1
From: New Cumberland PA
Originally Posted by 1970 Dave
Bolts long enough would have to be a minimum of about 14 inches long--the ride height was just shy of 35 1/2 inches--and yes I have heard of the longer spring bolts?
I think we all want to see what a vette with a 14" lift kit in the rear looks like.
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Thread Starter
Burning Brakes
Joined: Apr 2000
Posts: 1,012
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From: Minnesota
Originally Posted by mandm1200
If the spring was made to OEM specs, longer spring bolts should not be needed. I believe you question is why the manufactures of replacement spring cannot duplicate a similiar spring or at least ship a spring that retains the same ride height as the original. I do not have any answers to that. I would guess it may be a lack of quality control. The make a spring and assume it's perfect when in fact there are many that are out of spec.
In your case, changing to an 8" bolt may provide a solution to a problem created by the spring manufacture. The TRW composite spring is totally different in that they ship 8" bolts knowing that they will be needed. The problem with some of these springs is that the 8" bolts still do not provide enough length to lower the rear to an acceptable height. 10" bolts are needed which causes other issuses and may be unsafe due to tire and suspension issues. Muskegon is in the process of doing some testing and is to report back to the forum in the next few days according to the post in this thread, http://forums.corvetteforum.com/show...&page=18&pp=20 .
In your case, changing to an 8" bolt may provide a solution to a problem created by the spring manufacture. The TRW composite spring is totally different in that they ship 8" bolts knowing that they will be needed. The problem with some of these springs is that the 8" bolts still do not provide enough length to lower the rear to an acceptable height. 10" bolts are needed which causes other issuses and may be unsafe due to tire and suspension issues. Muskegon is in the process of doing some testing and is to report back to the forum in the next few days according to the post in this thread, http://forums.corvetteforum.com/show...&page=18&pp=20 .
I pulled out the 9 leaf and went with a 7 leaf F-41 type and it lowered it to just shy of 29 and with an 8 inch bolt I could adjust it to about 27 3/4--but why should I have to do that--if we bought a stock manifold or whatever and it wouldn't fit and the supplier said "just put in longer bolts" I think most of us wouldn't be happy. That was what I was trying to get at.
SEMPER FI--1970 Dave
Last edited by 1970 Dave; Feb 23, 2005 at 03:08 PM.
Tech Contributor
Joined: Aug 1999
Posts: 15,173
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From: Connecticut, USA
I've purcahsed several over the past 3-4 years both 7 & 9 leaf, made in Mexico or Canada. None of them were able to use the stock bolts all needed 8" bolts.
Danny at Van Steel said he has a source for correctly arched springs that will retain the correct height and stock bolts. Dan please correct if this is an incorrect statement.
Gary
Danny at Van Steel said he has a source for correctly arched springs that will retain the correct height and stock bolts. Dan please correct if this is an incorrect statement.
Gary
Drifting
Joined: Mar 2003
Posts: 1,608
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From: Canberra AUSTRALIA
St. Jude Donor '05-'06
Originally Posted by JohnS_77
I bought a 7 leaf from Zip, and it lowered the car in the rear. $109.
I need SHORTER bolts... To raise the ride height.
I need SHORTER bolts... To raise the ride height.
There are at least 100 people on the forum who wish they had that problem.
If you tighten up on the nuts you will gain height. You can also buy those Grade 8 bolts from most industrial fastener suppliers. Be sure to drill a hole for your retainer pin.
Last edited by stingry; Feb 23, 2005 at 05:46 PM. Reason: wrong word!!
Thread Starter
Burning Brakes
Joined: Apr 2000
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From: Minnesota
An interesting followup---I received an e-mail that said part of my problem was that I did not allow the 9 leaf to settle by driving it a few miles under different conditions--kinda hard when there is still darn near 18 inches of snow up here in Northern MN--but he added it probably would still have not been enough to meet my requirements--so in theory this 7 leaf that is now sitting at about 27 3/4 might even be a little low after the "drive around settle theory" but being I have the 8 inch bolt I can raise it some--ha ha ha
SEMPER FI--1970 Dave
SEMPER FI--1970 Dave
